RESUMO
Among FOS-related components of the dimeric AP-1 transcription factor, the oncoprotein FRA-1 (encoded by FOSL1) is a key regulator of invasion and metastasis. The well-established FRA-1 pro-invasive activity in breast cancer, in which FOSL1 is overexpressed in the TNBC (Triple Negative Breast Cancer)/basal subtypes, correlates with the FRA-1-dependent transcriptional regulation of EMT (Epithelial-to-Mesenchymal Transition). After summarizing the major findings on FRA-1 in breast cancer invasiveness, we discuss the FRA-1 mechanistic links with EMT and cancer cell stemness, mediated by transcriptional and posttranscriptional interactions between FOSL1/FRA-1 and EMT-regulating transcription factors, miRNAs, RNA binding proteins and cytokines, along with other target genes involved in EMT. In addition to the FRA-1/AP-1 effects on the architecture of target promoters, we discuss the diagnostic and prognostic significance of the EMT-related FRA-1 transcriptome, along with therapeutic implications. Finally, we consider several novel perspectives regarding the less explored roles of FRA-1 in the tumor microenvironment and in control of the recently characterized hybrid EMT correlated with cancer cell plasticity, stemness, and metastatic potential. We will also examine the application of emerging technologies, such as single-cell analyses, along with animal models of TNBC and tumor-derived CTCs and PDXs (Circulating Tumor Cells and Patient-Derived Xenografts) for studying the FRA-1-mediated mechanisms in in vivo systems of EMT and metastasis.
Assuntos
MicroRNAs , Neoplasias de Mama Triplo Negativas , Animais , Humanos , Linhagem Celular Tumoral , Movimento Celular , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Metástase Neoplásica , Fator de Transcrição AP-1/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente TumoralRESUMO
The initial conditions for morphogenesis trigger a cascade of events that ultimately dictate structure and functions of tissues and organs. Here we report that surface nanopatterning can control the initial assembly of focal adhesions, hence guiding human mesenchymal stem cells (hMSCs) through the process of self-organization and differentiation. This process self-sustains, leading to the development of macroscopic tissues with molecular profiles and microarchitecture reminiscent of embryonic tendons. Therefore, material surfaces can be in principle engineered to set off the hMSC program toward tissuegenesis in a deterministic manner by providing adequate sets of initial environmental conditions.
Assuntos
Adesões Focais/fisiologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Nanoestruturas/química , Tendões/crescimento & desenvolvimento , Engenharia Tecidual/métodos , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Teste de Materiais , Nanoestruturas/ultraestrutura , Propriedades de Superfície , Tendões/citologiaRESUMO
Most models of language comprehension assume that the linguistic system is able to pre-activate phonological information. However, the evidence for phonological prediction is mixed and controversial. In this study, we implement a paradigm that capitalizes on the fact that foreign speakers usually make phonological errors. We investigate whether speaker identity (native vs. foreign) is used to make specific phonological predictions. Fifty-two participants were recruited to read sentence frames followed by a last spoken word which was uttered by either a native or a foreign speaker. They were required to perform a lexical decision on the last spoken word, which could be either semantically predictable or not. Speaker identity (native vs. foreign) may or may not be cued by the face of the speaker. We observed that the face cue is effective in speeding up the lexical decision when the word is predictable, but it is not effective when the word is not predictable. This result shows that speech prediction takes into account the phonological variability between speakers, suggesting that it is possible to pre-activate in a detailed and specific way the phonological representation of a predictable word.
RESUMO
Background: Many data were published about Long-Covid prevalence, very few about the findings of new cardiac alterations (NCA) in COVID-19-recovered people. ARCA-post-COVID is an observational study designed to investigate the prevalence of NCA in patients recovered from Covid-19.Methods: from June 2020 to December 2022, we enrolled 502 patients with a positive nasopharyngeal swab for SARS-CoV2 and a subsequent negative one. We performed anamnesis, lab-test, and routine cardiological tests (ECG, Holter, TTE). Results: The median age was 56 years (IQR 44-67); women were 52.19%; in the acute phase 24.1% of patients were treated in a medical department, 7.2% in the ICU and the others at home. At the visit, 389 patients (77.49%) complained of a broad range of symptoms. We reported patients' characteristics according to the course of the disease and the persistence of symptoms. NCA were found in 138 patients (27.49%): among them 60 cases (11.95%) of pericardial effusion. Patients with NCA were older (median 60y, IQR: 47-72, vs median 56y, IQR 42-65), had a higher prevalence of smokers (27% vs 17%; p0.014), CAD (11% vs 6%; p0.048) and stroke/TIA (3.6% vs 0.3%; p0.002) and a lower prevalence of hypercholesterolemia (18% vs 30%; p0.007). The prevalence of NCA seems constant with different subtypes of the virus. Conclusion: the prevalence of NCA in patients who recovered from COVID-19 is high and constant since the beginning of the pandemic; it is predictable based on hospitalization and long-lasting symptoms (9.64%-42.52%). Patients with one of these characteristics should undergo cardiological screening.
RESUMO
We report the case of an 89-year-old female patient who presented to the emergency department after out-of-hospital cardiac arrest due to polymorphic ventricular tachycardia treated by public access defibrillation. The admission electrocardiogram (ECG) showed extreme QT prolongation (650 milliseconds) with recurrent episodes of nonsustained polymorphic ventricular tachycardia. Intravenous magnesium sulfate therapy was instituted. After history taking, it was found that the patient was on citalopram and that, 2 days prior to admission, she had begun treatment with levosulpiride. This drug combination resulted in marked prolongation of the QT interval that triggered the electrical storm.
Assuntos
Citalopram/efeitos adversos , Antagonistas dos Receptores de Dopamina D2 , Parada Cardíaca Extra-Hospitalar/induzido quimicamente , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Sulpirida/análogos & derivados , Idoso de 80 Anos ou mais , Interações Medicamentosas , Eletrocardiografia , Serviço Hospitalar de Emergência , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/fisiopatologia , Sulpirida/efeitos adversosRESUMO
Billions of years of co-evolution has made mitochondria central to the eukaryotic cell and organism life playing the role of cellular power plants, as indeed they are involved in most, if not all, important regulatory pathways. Neurological disorders depending on impaired mitochondrial function or homeostasis can be caused by the misregulation of "endogenous players", such as nuclear or cytoplasmic regulators, which have been treated elsewhere. In this review, we focus on how exogenous agents, i.e., viral pathogens, or unbalanced microbiota in the gut-brain axis can also endanger mitochondrial dynamics in the central nervous system (CNS). Neurotropic viruses such as Herpes, Rabies, West-Nile, and Polioviruses seem to hijack neuronal transport networks, commandeering the proteins that mitochondria typically use to move along neurites. However, several neurological complications are also associated to infections by pandemic viruses, such as Influenza A virus and SARS-CoV-2 coronavirus, representing a relevant risk associated to seasonal flu, coronavirus disease-19 (COVID-19) and "Long-COVID". Emerging evidence is depicting the gut microbiota as a source of signals, transmitted via sensory neurons innervating the gut, able to influence brain structure and function, including cognitive functions. Therefore, the direct connection between intestinal microbiota and mitochondrial functions might concur with the onset, progression, and severity of CNS diseases.
Assuntos
COVID-19 , Doenças do Sistema Nervoso Central , Microbioma Gastrointestinal , Humanos , SARS-CoV-2 , Eixo Encéfalo-Intestino , MitocôndriasRESUMO
We report the case of a female patient presenting to the emergency department with postprandial syncope and atrial fibrillation. After amiodarone administration, the electrocardiogram showed marked QT prolongation associated with ventricular arrhythmias, including an episode of torsade de pointes requiring immediate electrical cardioversion. During history taking, the patient reported that she had been drinking large amounts of grapefruit juice regularly. The inhibition of amiodarone metabolism induced by grapefruit juice was responsible for enhancing the proarrhythmic effects of the drug with development of electrical storm.
Assuntos
Amiodarona/efeitos adversos , Bebidas/efeitos adversos , Citrus paradisi/efeitos adversos , Interações Alimento-Droga , Idoso de 80 Anos ou mais , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/terapia , Cardioversão Elétrica , Eletrocardiografia , Serviço Hospitalar de Emergência , Feminino , Humanos , Torsades de Pointes/induzido quimicamente , Torsades de Pointes/terapiaRESUMO
The genetic and epigenetic changes affecting transcription factors, coactivators, and chromatin modifiers are key determinants of the hallmarks of cancer. The acquired dependence on oncogenic transcriptional regulators, representing a major determinant of cancer cell vulnerability, points to transcription factors as ideal therapeutic targets. However, given the unavailability of catalytic activities or binding pockets for small-molecule inhibitors, transcription factors are generally regarded as undruggable proteins. Among components of the AP-1 complex, the FOS-family transcription factor Fra-1, encoded by FOSL1, has emerged as a prominent therapeutic target. Fra-1 is overexpressed in most solid tumors, in response to the BRAF-MAPK, Wnt-beta-catenin, Hippo-YAP, IL-6-Stat3, and other major oncogenic pathways. In vitro functional analyses, validated in onco-mouse models and corroborated by prognostic correlations, show that Fra-1-containing dimers control tumor growth and disease progression. Fra-1 participates in key mechanisms of cancer cell invasion, Epithelial-to-Mesenchymal Transition, and metastatic spreading, by driving the expression of EMT-inducing transcription factors, cytokines, and microRNAs. Here we survey various strategies aimed at inhibiting tumor growth, metastatic dissemination, and drug resistance by interfering with Fra-1 expression, stability, and transcriptional activity. We summarize several tools aimed at the design and tumor-specific delivery of Fra-1/AP-1-specific drugs. Along with RNA-based therapeutics targeting the FOSL1 gene, its mRNA, or cognate regulatory circRNAs, we will examine the exploitation of blocking peptides, small molecule inhibitors, and innovative Fra-1 protein degraders. We also consider the possible caveats concerning Fra-1 inhibition in specific therapeutic contexts. Finally, we discuss a recent suicide gene therapy-based approach, aimed at selectively killing the Fra-1-overexpressing neoplastic cells.
RESUMO
Among the major mechanisms involved in tumorigenesis, DNA methylation is an important epigenetic modification impacting both genomic stability and gene expression. Methylation of promoter-proximal CpG islands (CGIs) and transcriptional silencing of tumor suppressors represent the best characterized epigenetic changes in neoplastic cells. The global cancer-associated effects of DNA hypomethylation influence chromatin architecture and reactivation of repetitive elements. Moreover, recent analyses of cancer cell methylomes highlight the role of the DNA hypomethylation of super-enhancer regions critically controlling the expression of key oncogenic players. We will first summarize some basic aspects of DNA methylation in tumorigenesis, along with the role of dysregulated DNA methyltransferases and TET (Ten-Eleven Translocation)-family methylcytosine dioxygenases. We will then examine the potential contribution of epimutations to causality and heritability of cancer. By reviewing some representative genes subjected to hypermethylation-mediated silencing, we will survey their oncosuppressor functions and roles as biomarkers in various types of cancer. Epithelial-to-mesenchymal transition (EMT) and the gain of stem-like properties are critically involved in cancer cell dissemination, metastasis, and therapeutic resistance. However, the driver vs passenger roles of epigenetic changes, such as DNA methylation in EMT, are still poorly understood. Therefore, we will focus our attention on several aspects of DNA methylation in control of EMT and metastasis suppressors, including both protein-coding and noncoding genes.
Assuntos
Transformação Celular Neoplásica/genética , Metilação de DNA , Transição Epitelial-Mesenquimal/genética , Genes Supressores de Tumor , Neoplasias/etiologia , Animais , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , MicroRNAs/genética , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas , Interferência de RNARESUMO
Among the FOS-related members of the AP-1 dimeric complex, the transcription factor Fra-1, encoded by FOSL1, is crucially involved in human tumor progression and metastasis, thus representing a promising therapeutic target. Here we review the state of the art and discuss the emerging topics and perspectives on FOSL1 and its gene product. First, we summarize the present knowledge on the FOSL1 transcriptional and epigenetic controls, driving Fra-1 accumulation in a variety of human solid tumors. We also present a model on the regulatory interactions between Fra-1, p53, and miRNAs. Then, we outline the multiple roles of Fra-1 posttranslational modifications and transactivation mechanisms of select Fra-1 target genes. In addition to summarizing the Fra-1-dependent gene networks controlling proliferation, survival, and epithelial-mesenchymal transitions (EMT) in multiple cancer cell types, we highlight the roles played by Fra-1 in nonneoplastic cell populations recruited to the tumor microenvironment, and in mouse models of tumorigenesis. Next, we review the prognostic power of the Fra-1-associated gene signatures, and envisage potential strategies aimed at Fra-1 therapeutic inhibition. Finally, we discuss several recent reports showing the emerging roles of Fra-1 in the mechanisms of both resistance and addiction to targeted therapies.
Assuntos
Transformação Celular Neoplásica/genética , Neoplasias/genética , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-fos/genética , Animais , Proliferação de Células/genética , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , MicroRNAs/genética , Metástase Neoplásica/patologia , Processamento de Proteína Pós-Traducional/genética , Microambiente Tumoral/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Collagen prolyl hydroxylation (CPH), which is catalyzed by prolyl 4-hydroxylase (P4H), is the most prevalent posttranslational modification in humans and requires vitamin C (VitC). Here, we demonstrate that CPH acts as an epigenetic modulator of cell plasticity. Increased CPH induced global DNA/histone methylation in pluripotent stem and tumor cells and promoted cell state transition (CST). Interfering with CPH by either genetic ablation of P4H subunit alpha-2 (P4HA2) or pharmacologic treatment reverted epigenetic changes and antagonized CST. Mechanistically, we suggest that CPH modifies the epigenetic landscape by reducing VitC for DNA and histone demethylases. Repurposed drugs targeting CPH-mediated metabolic perturbation, such as the antiasthmatic budesonide, blocked metastatic dissemination of breast cancer cells in vivo by preventing mesenchymal transition. Our study provides mechanistic insights into how metabolic cues and epigenetic factors integrate to control CST and paves the way for the development of novel antimetastatic strategies. SIGNIFICANCE: A phenotype-based high-throughput screening reveals unforeseen metabolic control of cell plasticity and identifies budesonide as a drug candidate for metastatic cancer.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/13/3235/F1.large.jpg.
Assuntos
Neoplasias da Mama/patologia , Colágeno/metabolismo , Epigênese Genética , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Células-Tronco Pluripotentes/patologia , Prolil Hidroxilases/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Hidroxilação , Células-Tronco Pluripotentes/metabolismo , Prolil Hidroxilases/genéticaRESUMO
OBJECTIVE: To report our data on selected patients with previous paradoxical embolism who underwent transcatheter patent foramen ovale (PFO) closure. METHODS: Between July 2001 and July 2007, percutaneous PFO closure was performed on 128 patients (65 women, mean age: 46 +/- 12.8 years). Patent foramen ovale closure was recommended for secondary prevention in patients with previous transient ischemic attacks (52.5%), stroke (46%), or peripheral embolism (1.5%). RESULTS: Implantation was successful in all patients, and at the end of intervention, complete PFO closure was achieved in 70.3% of them. There were no "major" complications (ie, deaths, device embolization or thrombosis, need for cardiac surgery). The overall incidence of complications (mostly hemorrhagic) was 7%. The mean follow-up period was 32 months. Complete closure had been achieved in 78.4% and in 82.5% of patients at the third month of transesophageal echocardiography examination and at the sixth month of transcranial Doppler examination, respectively. There were no recurrent thromboembolic events during the follow-up period. CONCLUSIONS: Percutaneous closure of PFO is a feasible procedure, but it is not a risk-free technique. However, in correctly selected patients (ie, large PFO and those at risk for neurologic relapse), nearly complete PFO closure seems to provide protection from future neurologic ischaemic events at midterm follow-up.
Assuntos
Cateterismo Cardíaco , Embolia Paradoxal/etiologia , Forame Oval Patente/terapia , Adulto , Embolia/etiologia , Embolia/terapia , Feminino , Seguimentos , Forame Oval Patente/complicações , Humanos , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/terapia , Masculino , Pessoa de Meia-Idade , Próteses e Implantes , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Resultado do TratamentoRESUMO
The AP-1 transcription factor plays an essential role in cell proliferation and tumorigenesis. It was previously shown that the fra-1 gene product is upregulated by various oncogenes and is involved in the in vitro and in vivo transformation of thyroid cells. Here we show that the ras oncogene-dependent accumulation of Fra-1 is mediated by a positive feedback mechanism which requires both transcriptional autoregulation and posttranslational stabilization of the protein. The oncogene-dependent transcriptional activation involves the cooperation between both Raf-dependent and Raf-independent pathways and is mediated by an AP-1 site within the fra-1 first intron, which becomes stably occupied by a transcriptionally active Fra-1-containing complex in ras-transformed cells. The posttranslational stabilization results in a drastic increase in the Fra-1 half-life in ras-transformed cells and is totally dependent on the activity of the MEK/ERK phosphorylation pathway. The analysis of the Fra-1 transactivation potential shows that the protein is able to stimulate a heterologous promoter in a ras-dependent manner, but the transactivating activity requires the recruitment of a heterodimeric partner. These data show that the alteration of multiple regulatory mechanisms is required for the constitutive activation of Fra-1 as a nuclear target of ras transformation.
Assuntos
Regulação da Expressão Gênica , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Transcrição Gênica , Proteínas ras/metabolismo , Animais , Northern Blotting , Linhagem Celular , Linhagem Celular Transformada , Núcleo Celular/metabolismo , Cromatina/metabolismo , Cromatografia , DNA/metabolismo , Dimerização , Immunoblotting , Íntrons , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Modelos Genéticos , Mutação , Reação em Cadeia da Polimerase , Testes de Precipitina , Ligação Proteica , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Ativação Transcricional , Regulação para CimaRESUMO
BACKGROUND: Non-vitamin K antagonist oral anticoagulants, including dabigatran, are currently widely used for the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation. Recently, idarucizumab, a monoclonal antibody fragment for immediate reversal of dabigatran-induced anticoagulation, has been introduced into the market to be used in life-threatening bleeding or urgent surgery, allowing for rapid normalization of clotting parameters. The use of idarucizumab is not yet well established in patients presenting with acute ischemic stroke on dabigatran who are candidates for thrombolytic therapy. CASE PRESENTATION: We report the case of a 71-year-old hypertensive Caucasian woman with non-valvular atrial fibrillation treated with dabigatran 150 mg twice daily, who presented with acute ischemic stroke causing right-sided hemiparesis and aphasia. Two hours after presentation to the emergency department, a decision was made to administer idarucizumab for achieving complete reversal of any potential anticoagulant effect of dabigatran and, in the absence of any contraindications, our patient underwent successful thrombolysis. At discharge, our patient was able to walk unassisted and had only residual aphasia. Twenty days later, she had completely recovered motor function of her right side, with further progressive improvement of aphasia. Repeat cranial computed tomography confirmed the absence of hemorrhage, and anticoagulant therapy with dabigatran 150 mg twice daily was resumed. CONCLUSIONS: Our case report adds to the evidence that idarucizumab administration is safe in the setting of patients with atrial fibrillation treated with dabigatran who develop acute ischemic stroke requiring thrombolysis.
Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antitrombinas/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Isquemia Encefálica/terapia , Dabigatrana/uso terapêutico , Acidente Vascular Cerebral/cirurgia , Terapia Trombolítica/métodos , Administração Intravenosa , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Antitrombinas/efeitos adversos , Isquemia Encefálica/tratamento farmacológico , Dabigatrana/efeitos adversos , Interações Medicamentosas , Feminino , Humanos , Hipertensão/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do TratamentoRESUMO
Hypopituitarism reduces life expectancy and increases the risk of cardiovascular and cerebrovascular diseases, as well as death. Abnormalities in the cardiovascular system may be independently related to GH deficiency (GHD). The aim of this study was to prospectively investigate coronary flow reserve and diastolic function in GHD adult patients at diagnosis and after 1 year of GH replacement therapy. As control group, an age- and sex-matched population was chosen. All patients and controls were non-smokers, non-diabetic, and normotensive, with no history of vascular disease. 14 patients with adult-onset GHD and 17 controls represent the two study groups. Anthropometric data, blood pressure, lipid profile, glycosylated hemoglobin (HbA1c) and IGF-I plasma levels, coronary flow reserve (CFR), and LV diastolic function (evaluated by E/A) were collected in all subjects before and after 12 months of GH replacement therapy. Compared with controls, systolic and diastolic blood pressure and LDL cholesterol levels were significantly higher at baseline and return, comparable to controls after 1 year of GH replacement (GHRT). GHD patients showed a blunted CFR at baseline (P < 0.001) and a significant improvement after GHRT, returning to values comparable with those recorded in the control group. In addition, after therapy a significant (P < 0.001) improvement in E/A was recorded. One year of GH therapy improves CFR and E/A in the patient population analyzed, thereby encouraging the early start of GHRT.
Assuntos
Pressão Sanguínea/fisiologia , Circulação Coronária/fisiologia , Coração/fisiopatologia , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Hipopituitarismo/tratamento farmacológico , Adulto , Idoso , Ecocardiografia , Feminino , Hemoglobinas Glicadas/metabolismo , Hormônio do Crescimento Humano/deficiência , Humanos , Hipopituitarismo/sangue , Hipopituitarismo/fisiopatologia , Fator de Crescimento Insulin-Like I/metabolismo , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Exploitation of embryonic stem cells (ESC) for therapeutic use and biomedical applications is severely hampered by the risk of teratocarcinoma formation. Here, we performed a screen of selected epi-modulating compounds and demonstrate that a transient exposure of mouse ESC to MS-275 (Entinostat), a class I histone deacetylase inhibitor (HDAC), modulates differentiation and prevents teratocarcinoma formation. Morphological and molecular data indicate that MS-275-primed ESCs are committed towards neural differentiation, which is supported by transcriptome analyses. Interestingly, in vitro withdrawal of MS-275 reverses the primed cells to the pluripotent state. In vivo, MS275-primed ES cells injected into recipient mice give only rise to benign teratomas but not teratocarcinomas with prevalence of neural-derived structures. In agreement, MS-275-primed ESC are unable to colonize blastocysts. These findings provide evidence that a transient alteration of acetylation alters the ESC fate.
RESUMO
The use of Embryonic Stem Cells (ESCs) holds considerable promise both for drug discovery programs and the treatment of degenerative disorders in regenerative medicine approaches. Nevertheless, the successful use of ESCs is still limited by the lack of efficient control of ESC self-renewal and differentiation capabilities. In this context, the possibility to modulate ESC biological properties and to obtain homogenous populations of correctly specified cells will help developing physiologically relevant screens, designed for the identification of stem cell modulators. Here, we developed a high throughput screening-suitable ESC neural differentiation assay by exploiting the Cell(maker) robotic platform and demonstrated that neural progenies can be generated from ESCs in complete automation, with high standards of accuracy and reliability. Moreover, we performed a pilot screening providing proof of concept that this assay allows the identification of regulators of ESC neural differentiation in full automation.
Assuntos
Automação Laboratorial/métodos , Diferenciação Celular , Ensaios de Triagem em Larga Escala/métodos , Células-Tronco Neurais/citologia , Animais , Linhagem Celular , Células-Tronco Embrionárias/citologia , Camundongos , Neurônios/citologia , Projetos Piloto , Reprodutibilidade dos TestesRESUMO
The molecular mechanisms controlling mouse embryonic stem cell (ESC) metastability, i.e. their capacity to fluctuate between different states of pluripotency, are not fully resolved. We developed and used a novel automation platform, the Cell(maker), to screen a library of metabolites on two ESC-based phenotypic assays (i.e. proliferation and colony phenotype) and identified two metabolically related amino acids, namely l-proline (l-Pro) and l-ornithine (l-Orn), as key regulators of ESC metastability. Both compounds, but mainly l-Pro, force ESCs toward a novel epiblast stem cell (EpiSC)-like state, in a dose- and time-dependent manner. Unlike EpiSCs, l-Pro-induced cells (PiCs) contribute to chimeric embryos and rely on leukemia inhibitor factor (LIF) to self-renew. Furthermore, PiCs revert to ESCs or differentiate randomly upon removal of either l-Pro or LIF, respectively. Remarkably, PiC generation depends on both l-Pro metabolism (uptake and oxidation) and Fgf5 induction, and is strongly counteracted by antioxidants, mainly l-ascorbic acid (vitamin C, Vc). ESCs â PiCs phenotypic transition thus represents a previously undefined dynamic equilibrium between pluripotent states, which can be unbalanced either toward an EpiSC-like or an ESC phenotype by l-Pro/l-Orn or Vc treatments, respectively. All together, our data provide evidence that ESC metastability can be regulated at a metabolic level.
Assuntos
Células-Tronco Embrionárias/metabolismo , Prolina/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Células Cultivadas , Células-Tronco Embrionárias/citologia , Feminino , Humanos , Masculino , Camundongos , Camundongos SCID , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismoRESUMO
OBJECTIVES: Growing evidence supports the role played by inflammation in atherosclerosis. Identifying sensitive biomarkers is useful in predicting accelerated atherosclerosis. We investigated prospectively the relationship between plasma levels of inflammatory biomarkers [osteopontin, C-reactive protein (CRP), interleukin-6 (IL-6)] and instent restenosis, and rapid coronary plaque progression in patients with coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI). METHODS: We studied 77 patients with CAD: 45 affected by unstable angina/non-ST elevation myocardial infarction [acute coronary syndrome (ACS)], and 32 by chronic coronary syndrome (CCS). Plasma osteopontin, IL-6, and CRP levels were measured before intervention in all patients; measurements were carried out on the basis of the following time course at 1,15, 30, 90, and 180 days follow-up in a subgroup of 39 consenting patients. Clinical and biohumoral data were correlated with baseline and 6-month PCI follow-up angiography. RESULTS: Osteopontin, IL-6, and CRP were higher in patients with ACS than in those with CCS (analysis of variance: P<0.001, 0.05, and 0.05, respectively). Baseline osteopontin levels proved to be associated with rapid coronary plaque progression (P=0.005) and instent restenosis (P=0.05). The highest osteopontin levels were found in patients with CAD with both rapid plaque progression and instent restenosis (P=0.003). PCI increased inflammatory markers acutely, and osteopontin remained elevated in patients with ACS. Patients with ACS showed a higher percentage (74%) of rapid plaque progression than those with CCS (26%) (P<0.05). CONCLUSION: The study prospectively shows the link between inflammatory status and accelerated atherosclerosis in patients with CAD undergoing PCI. The baseline and persistent rise of osteopontin is an expression of its contribution to the accelerated plaque progression, and therefore osteopontin may be a useful prognostic biomarker.
Assuntos
Angioplastia Coronária com Balão , Aterosclerose/sangue , Aterosclerose/fisiopatologia , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/terapia , Osteopontina/sangue , Idoso , Aterosclerose/etiologia , Biomarcadores/sangue , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Reestenose Coronária/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Estudos ProspectivosRESUMO
We report a case of left atrial myxoma presenting as acute respiratory failure following surgical intervention for voluntary interruption of pregnancy. After cardiac surgery T-wave changes were observed on the ECG, most likely due to coronary embolism.